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Considering the cost of piece milling the engine, you may wish to consider the new Edlebrock Super Charged 350 crate that cranks out over 500 hp. Might not cost any more than what you'll have in that 383 with EFI and SuperCharger...Just a thought....

04-20-2004 07:01 AM

Noesis

Just revieweing my options. Thanks for all the info.

04-19-2004 09:10 PM

camaroman7d

I think I am missing something here. Are you talking about getting a crate engine and then adding the supercharger to that?

If so I think you will basically be in the same place you are now, unless you are going to have an engine built to take advantage of the blower you will be in the same boat.

By skipping or holding off on the fuel injection that can save you a few bucks and make things a little more simple. Once that is sorted out you could always add fuel injection later.

If you/he wants a blown engine the basic rules are (if he wants to make power), forged pistons, good rod/s bolts, forged crank, and low compression 9:1 or less. If you have those basic things then typically you can bolt a blower on and make decent power.

If you are looking at a GM crate engine I don't know of one that fits that description, there may be one I just don't know what all they have to offer these days.

There are a couple places that offer ready built blown engines Bad ***** Racing Engines (Sonoma, Ca) and Speedomotive (Southern Cal)are two that come to mind.

I am not sure what you are thinking at this point?

Royce

04-19-2004 07:50 PM

Noesis

Thanks for the great information.

Do you think he would be better off just to get a new crate motor instead of spending the money to fuel inject this and get it ready for a blower?

-Chad

04-19-2004 03:03 PM

camaroman7d

The reason I went with the larger supercharger is, so I could make the same or more boost and not heat up the charge as much. This means more power and less chance of detonation.

The smaller the blower the faster you have to spin it to make the same boost as a larger blower. The faster you spin them the more heat they make and heat up the intake charge. When the charge is heated it doesn't make as much power and has more tendancy to detonate. With my 8-71 I can make 12lbs of boost at 10% underdriven (blower turning 10% slower than the crankshaft). With a 6-71 I would have to probably run it slightly overdriven to accomplish the same thing. This is all done by the pulleys you choose. A 6-71 is usually plenty for most small blocks and mild big blocks. The 8-71 was a little more money up front but, it leaves room to grow as well. My goal was to make as much power as possible on pump gas so the 8-71 was right for me.

Sorry for the long winded response, I just like to make sure things are clear.

Royce

04-19-2004 02:37 PM

87442lover

Hey, camaroman, why did you go with an 871 over a 671 again? Curious.

04-19-2004 02:24 PM

camaroman7d

There is some info I supplied for a guy that was thinking about building/adding a supercharger to a 350 the same basic rules still apply to a 383 (it is at the bottom of the post). I have a blown 388 with a 8-71 Hampton blower. While I chose to go with carbs, there is no reason not to run injection, the initial price is higher but, the added tuneability and efficientcy will be better with injection (once you get it sorted out).

You do NOT need to get rid of the leaf springs. There are leaf spring cars running in the 8's with 10" tires. The bars 87442lover were thinking about are ladder bars or 4-link, neither is a must. Both have certain advantages and dis-advantages. A pair of Cal-Tracs could be more than enough. I personally made a set of traction bars and still have the worn out leafs with a pair of 12-way adjustable coil overs. The leafs are only thre to keep the rear end centered.

Judging by the way you asked the question, it seems like very little is known about the vehicle in question. There is a lot more to supercharging an engine than most people think. Botling it on is the easy part but, if you want to make power there are a lot of things that need to be thought about. Read the post I am providing below:

"If you want a top quality blower I HIGHLY recommend www.hamptonblowers.com There IS a difference in blowers. I did a lot of research (years worth) before buying my blower.

You have gotten some very good advice so far but, I would like to add a few things.

If you are going to do it you might as well make some power, it's not going to cost much more. Your goal will be VERY easy to reach. Keep the compression in the 8-8.5:1 range and go with good rods and forged pistons. I would also recommend contacting Engle Racing cams www.englecams.com and having a talk with them about your goals and they will grind you a cam that fits your needs. You will need a cam with a LSA of 112-114 that is really about the only hard and fast rule. You don't want a lot of overlap.

As far as the crank hub or balancer it is a matter of opinion (which you will see a lot of when it comes to blown applications) I chose to go with Hampton and followed his advice (he has been doing it longer than anyone and really knows his stuff). I went with a crank hub. The problem with a balancer on a SBC is that the crank snout is so small (in diameter) that you don't want to hang a lot of weight on it (ie...a balancer) when using a blower. I would also recommend going with an 8mm drive and not a 1/2" pitch, the 8mm will make slightly more power but, the main thing is it will put less stress on the crank snout. As you can see there is a lot to thing about feel free to ask more questions as you venture deeper into this project.

I HIGHLY recommend going with Holley blower carbs as well. You can get away with a standard carb but, if you are going to do it you might as well do it "right" (matter of opinion as well). The guys at www.allcarbs.com (All State Carbs) are great to work with and I used them and recommend others to them as well (If you go that route tell them Royce sent you).

For headgaskets I would recommend Cometic MLS gaskets (you do not need to O ring the heads with their gaskets and they seal better than copper. Some machine shops are not up on these gaskets yet and might try to tell you that O ringing is needed (IT"S NOT) especially on a street engine making less than 18lbs of boost. If you keep the boost under 10-12lbs I know of some people getting by with standard composite head gaskets (I personally wouldn't try it).

If your GM ignition is an HEI style it might be a tight fit with the blower, you don't have to have an exotic ignition for a mild blown engine, but you do want plenty of fire. If you plan on pushing the limits I would recommend a Crane ignition/boost retard or MSD ignition/boost retard.

As you can see there is WAY too much info to post it all here, hopefully this gave you some things to think about and decide if you want to go deeper."

Royce

04-19-2004 07:00 AM

87442lover

As for the engine, I would go with a GM TBI kit, they can be found complete for around $850 or so, and then run a centrifugal blower. As far as lag with a centrifugal, I dont think so, I like them. You could always just up the pulley ratio, or gear ratio to improve when the paxton comes alive.

If your going for a 671, or 871 I would stick to carburation. You'll find the benefits of tuning them with out eprom reprograming very helpful.

Now just because it's a 70 you'll have to either replace the leaf springs with coil, and/or add... ahh.. what do they call them, those damn arms, my brain just stopped working. Otherwise you'll twist the rearend up.

04-19-2004 06:44 AM

Noesis

It's a 1970 something camaro...

Any specific recommendations on parts?

Money is a consideration, so good parts for the money is what we are looking for, but he can afford to do things right.

-Chad

04-18-2004 10:39 PM

DoubleVision

All I`ll say is, your friend must have a lot of cash. You`ll have to run a compression check to see what it is, that or find which pistons are in the engine and what chamber size in cc`s the heads are, if you plan to go with a blower, the compression will have to be lowered to around the 8:1 area, you`ll need forged blower pistons, and you`ll need a good set of rods, stockers won`t cut it, if it`s a 2 bolt block I would move to a 4 bolt, if the crank is a stock chevy 400 unit, I would go to a eagle or scat aftermarket crank, I would also order a internally balanced unit and I would have the whole rotating assembly balanced afterwards. if the car doesn`t have subframe connectors it will be very much in need of them or body flex will occur along with possible windshield breakage. If the car is a 82 - 93 model, the stock rear won`t cut it either, the stocker rear of these years isn`t even strong enough for a 383 yet alone a 383 that`s blown.

04-18-2004 08:34 PM

Noesis

Supercharging and fuel injecting a 383 Chevy

My friend just bought a Camaro with a 383 in it. I don't know much about the engine yet.... 400 crank I think with the 4.030 bore and 3.760 stroke. It's carburated.

My question is this....

This Camaro is one he wants to drive around on weekends. He wants it to be driveable. But he also wants to drag race it. So I want to find a happy medium for him.

First, we want to fuel inject it. For driveablity and the obvious benefits. What are my options?

....and supercharge it (if possible). What's the initial compression ratio on a 383? I was thinking a 471 or a 671 roots blower (BDS)? Or perhaps a centrifugal... like a Paxton NOVI-2000 Race?

For a drag race setup will the lag of the centrifugal become a problem? what do you guys think? I know the centrifugals are more effecient and I know we could go into a huge battle about what is better, but, I'm a little lost at what to do. The roots will definetly come on quicker, but will it make the power up top that the centrifugal will and I could get it to start making boost quickly..... plus with a stroker like a 383 the low end grunt should make traction interesting anyways, right?

Thanks for any help! any tips on making this 383 make some serious power would be great!! I've been searching the forums here for other 383 information and that has been really helpful too!